--- libtorrent-0.12.2.orig/src/utils/diffie_hellman.cc	Wed May  7 12:19:12 2008
+++ libtorrent-0.12.2/src/utils/diffie_hellman.cc	Sun Jun 15 10:51:31 2008
@@ -47,6 +47,80 @@
 
 namespace torrent {
 
+static int generate_key(DH *dh)
+	{
+	int ok=0;
+	int generate_new_key=0;
+	unsigned l;
+	BN_CTX *ctx;
+	BN_MONT_CTX *mont=NULL;
+	BIGNUM *pub_key=NULL,*priv_key=NULL;
+
+	ctx = BN_CTX_new();
+	if (ctx == NULL) goto err;
+
+	if (dh->priv_key == NULL)
+		{
+		priv_key=BN_new();
+		if (priv_key == NULL) goto err;
+		generate_new_key=1;
+		}
+	else
+		priv_key=dh->priv_key;
+
+	if (dh->pub_key == NULL)
+		{
+		pub_key=BN_new();
+		if (pub_key == NULL) goto err;
+		}
+	else
+		pub_key=dh->pub_key;
+
+
+	if (dh->flags & DH_FLAG_CACHE_MONT_P)
+		{
+		mont = BN_MONT_CTX_set_locked((BN_MONT_CTX **)(&dh->method_mont_p),
+				CRYPTO_LOCK_DH, dh->p, ctx);
+		if (!mont)
+			goto err;
+		}
+
+	if (generate_new_key)
+		{
+		l = dh->length ? dh->length : BN_num_bits(dh->p)-1; /* secret exponent length */
+		if (!BN_rand(priv_key, l, 0, 0))
+			if (!BN_pseudo_rand(priv_key, l, 0, 0)) goto err;
+		}
+
+	{
+		BIGNUM local_prk;
+		BIGNUM *prk;
+
+		if ((dh->flags & DH_FLAG_NO_EXP_CONSTTIME) == 0)
+			{
+			BN_init(&local_prk);
+			prk = &local_prk;
+			BN_with_flags(prk, priv_key, BN_FLG_EXP_CONSTTIME);
+			}
+		else
+			prk = priv_key;
+
+		if (!dh->meth->bn_mod_exp(dh, pub_key, dh->g, prk, dh->p, ctx, mont)) goto err;
+	}
+
+	dh->pub_key=pub_key;
+	dh->priv_key=priv_key;
+	ok=1;
+err:
+	if (ok != 1) {
+	}
+
+	if ((pub_key != NULL)  && (dh->pub_key == NULL))  BN_free(pub_key);
+	if ((priv_key != NULL) && (dh->priv_key == NULL)) BN_free(priv_key);
+	BN_CTX_free(ctx);
+	return(ok);
+}
+
 DiffieHellman::DiffieHellman(const unsigned char *prime, int primeLength,
                              const unsigned char *generator, int generatorLength) :
   m_secret(NULL) {
@@ -56,7 +130,8 @@
   m_dh->p = BN_bin2bn(prime, primeLength, NULL);
   m_dh->g = BN_bin2bn(generator, generatorLength, NULL);
 
-  DH_generate_key(m_dh);
+  if (!generate_key(m_dh))
+    throw internal_error("Unable to generate encryption key.");
 #else
   throw internal_error("Compiled without encryption support.");
 #endif